#include <stdio.h>
#include <math.h>
int main()
{
    int n, a, i;
    printf(" the series with equal difference are:\n");
    for (n = 1; n <= 6; n++)
        for (a = 1; a <= 4; a++)
            if (4 * n + 6 * a == 26 && n * (n + a) * (n + a + a) * (n + a + a + a) == 880)
                for (i = 0; i < 20; i++)
                    printf("  %d",n+i*a);
}